The Human CastWhile the book tells the story through various first-person accounts of the epidemic, the filmmakers chose to tell the tale through one very special Everyman -- Gerry Lane, ex-U.N. investigator, played by Brad Pitt.

"Gerry has gone to hot zones around the world -- Rwanda, Bosnia -- places of tremendous danger and turbulence and crisis. Ultimately he retreats from that line of work to focus on his family and live a more normal life. But when the zombie outbreak occurs, his former employer contacts him believing he is the only man for the job. He is essentially trying to figure out the identity of Patient Zero -- where the epidemic really began and the whole movie is told through his point of view. It was really important for me that we build the movie around that; we experience everything as he does," Forster says.

In Brad Pitt, Forster says, he had the ideal ally, on and off the screen.

"It was an incredible experience working with Brad. He is a sublime actor and a true artist with impeccable taste, not just as the star of the film but also as the producer. His sensibility of what works, what is real versus what rings as false, is right on point. We're not making a documentary, we're making a film but at the same time, we wanted to keep it grounded in reality and he has a true sensitivity for that.Both of us had never done anything like this and in that sense it was a challenge - to work through this genre that was unfamiliar to the both of us and to try to create something fresh and new. I really enjoyed that tremendously, I couldn't have wished for a better partner," Forster says.

Forster's eclectic filmography intrigued Pitt.From action films to period biographies and book adaptations -- "He can't be pigeonholed as a director and his experience and interest in many genres and types of film is a rarity. His most memorable moments on film are intimate and human.It was this quality juxtaposed against our massive global apocalyptic crisis that we believed would lead to an unusually authentic and grounded action thriller."

Forster says that Gerry is "not your typical hero" and that is part of the character's appeal.

"Several times in the movie, Gerry says that movement is life and he urges people around him to keep moving. I like that phrase a lot, because ultimately in life we can't stand still, we have to move with the current otherwise we'll drown. But all the while he is observing and adjusting -- as the zombies take over, he sees little signs and starts to put things together. He makes crucial decisions in the moment. He is chosen for this journey because he has the unique ability to be thrown into extremely dangerous, chaotic situations and survive," Forster says.

This is not a life Gerry particularly enjoys so he gave it up to spend more time with his family. Ironically, to protect his family, he must return to his previous, perilous job.

"Gerry can't fly, he can't beat up bad guys...He has no super-powers.He's a dad, with a burning need to keep his family safe," says Pitt."To do that, he can only rely on his intellect, his instincts and his experience."

"It was very important to cast an actress as his wife Karen who had both strength and vulnerability. Because when he leaves, she must rise to the occasion so that their kids feel safe, even as everything around them is disintegrating. But also you need to feel that when she's alone, how much she misses him and fears that she won't ever see him again," Forster says.

Mireille Enos embodied those dual qualities of strength and vulnerability.

"She came in and did a reading that was so beautiful and truthful and she possessed all these different layers that I saw in the character," Forster says.

"World War Z" is the largest film Enos' has ever worked on, and she describes the experience as "thrilling and surprising," largely due to Forster's approach.
"Marc is such a gentle and thoughtful human being. He puts you completely at ease. There was so much respect, warmth and collaboration on set. It was a gift to work with someone who has that much grace. I was in this huge action film, and yet the scenes I got to do with Brad were intimate and subtle -- it was all those things because Marc is telling the story. He looks for those little 'human pearls,' that's what he calls them. It was the best of both worlds," Enos says.

Enos says her collaboration with Pitt was equally gratifying.

"He is a wonderfully generous, open actor who keeps it light -- he brings a lot of laughter on to the set. And you can see that he is always thinking about the story and the best way to tell it," Enos says.

"Mireille is a brilliant partner on set," says Pitt of his co-star."To keep a sense of freshness and to capture natural moments, many of the family scenes are riffed.This calls for a great understanding of the moment, and quick reflexive instincts.Mireille can embody the lovingness of the mother and flip to the ferociousness of the lioness protecting her young in an instant.As in any great relationship, she carried half the weight-a true ally."

Enos notes that while Karen understands that Gerry must leave the family, "... she has a lot of very mixed feelings about Gerry volunteering for this mission. On one hand, it would be excellent if he could help to solve this world crisis. But it also means that she is left alone with the children, in a world where survival is not easy. At the critical moment when she needs him the most, and they really need to band together - he steps away. It's complicated. And it ties into what Marc is trying to do with the movie, to look at the humanity within an incredibly dire situation. Not to get too heavy, but we are a world in crisis and Marc is making a smart film that makes us conscious of how delicate the human condition is."

"World War Z" initially highlights this "human condition" through the intimate relationship between Gerry and his family, who he reluctantly must abandon for their own sake. To that end, it was important that the opening scenes between Gerry, his wife and his young daughters, portrayed by Sterling Jerins and Abigail Hargrove, seem playful and loving and real. Audiences had to feel their bond immediately because the world as they know it is soon violently and terrifyingly upended.

"It was so critical to get that relationship right. We looked long and hard and found two girls that are very talented but who also act very much like their own age and look very much like their own age. And then we made a point to have the four of them spend time together as a familial unit so when they got on set, that was out of the way. They'd already met and they'd already played games and eaten together and done some things that families do so they wouldn't be distracted by meeting one another for the first time. It all came very naturally. Abigail is very much the older sister and Sterling is very much the younger sister and the baby of the family and Mireille is a parent and Brad is a parent, so there were a lot of boxes that were already checked. Beyond that, I think the best thing you can ever do to shore up dynamics like that in movies is to give them time to knit themselves together to be believable," Gardner says.

Thierry Umutoni, Gerry's friend and ex-boss, is the person who sets this double-edged, Faustian plan into motion -- he arranges to whisk the family to safety by airlifting them to a secure aircraft carrier, on the condition that Gerry, with his very specific skill set, embark on a mission to literally save the world. South African actor Fana Mokoena plays Thierry and "World War Z" is his second movie with Marc Forster.

"I worked with him on 'Machine Gun Preacher' and he's amazing. I come from a culture where directors are prescriptive and descriptive, but Marc trusts his actors. He gives you the leeway to explore and that's very liberating, especially in a movie of this magnitude. There's nothing better than when an actor is given the creative space to breathe and he (Marc) does that while also considering the bigger picture. He was always very sensitive to the actors, the story and the characters and brought that sensitivity to the whole project," Mokoena says.

Mokoena is also one of the only actors in the film to have scenes with both Enos and Pitt.

"It was fantastic to work with both of them. Brad does such quality work but is also a great student of humanity. And Mireille is such a wonderful person, always smiling, concerned about everyone around her. And such an amazing talent, she brings out the best in everyone. She's like a friend you want to have for life," Mokoena says.

In a North Korean military prison under siege, Gerry meets a corrupt and recently imprisoned CIA agent (David Morse) who may or may not be deranged.

"My character has become rather cynical in his view of the world. He has done something he's been punished for, but it's a punishment that probably saved his life because it lands him in a jail cell in Korea and protects him from the really terrifying things happening outside. The information he has helps Gerry move to the next step," Morse says.

From behind bars, he tells Gerry an outrageous and possibly true tale of his own first encounter with the virus and the way one nation chose to combat it.
Morse worked with Pitt on the film "Twelve Monkeys" and was delighted to reunite with him for this pivotal scene.

A wry, forthright Army Ranger, portrayed by James Badge Dale, runs the North Korean military installation. He follows his orders the best that he can while keeping his men alive in the face of the unspeakable anarchy exploding right outside his bunker.

"I am a big fan of David Morse, always have been. I had the pleasure of working with him before -- he's an incredibly gifted, humble, respectful actor. It was great just to watch him form this character, sitting in a prison cell, just trying things out. It is such a dynamic performance but on a moment's notice, he can turn it around and make it so small, internal and truthful. The man is incapable of lying, he is always so present, just fantastic," Badge Dale says.

He also enjoyed working with Pitt, in his dual actor/producer roles, both of which, he says, fed the other in a quiet, subtle way.

"If you didn't know he was the producer, you wouldn't because he doesn't wheel that around. What he does is come in as a caring artist. He cares about the story, about the cast and crew and he makes sure that everyone is comfortable. He's less concerned with himself than with everyone around him -- it's very selfless and creates a positive work environment," Badge Dale notes.

Badge Dale has some on-screen combat background, from his work in the HBO miniseries "The Pacific." However, this was an entirely new military experience for him and he relied on Freddie Joe Farnsworth, the seasoned stunt man and "World War Z" military technical advisor.

"I told Freddie I didn't need to go to boot camp but I did want to spend some time with the guys who would be my fellow soldiers. So Freddie took the time to explain the weapons to us and run some drills with us so we could get to know each other and bond," he explains.

Gerry's hunt takes him from Korea to Israel where he witnesses first hand their indigenous, time-honored form of containment and protection -- walls and barricades (some ancient, some new), all designed to keep their people safe. Until they don't, of course. Gerry's guide in Jerusalem is Jurgen Warmbrumm of the Mossad and even when the situation there deteriorates into violence and pandemonium, a combination of Gerry's instincts and experience allow him to get out safely while learning another piece of vital information in his search for answers. Israeli filmmaker Ludi Boeken plays Warmbrumm.

"I'm actually a film director and producer and developing another project with Marc. I happened to be meeting with him in London about it and as we were talking, Marc suddenly looked at me and -- even though we have known each other for a long time -- said, 'Have you ever acted in a movie? Would you read for me?' I said, 'Well, yeah, I've been in a few of my own movies, usually killers or bad guys.' And I think he also knew that I had worked as a war reporter in the Middle East, not just in Israel, and I've known people like Warmbrumm," Boeken says.

Daniella Kertesz, also from Israel, plays Segen, the Israeli Lieutenant who joins Gerry and becomes a critical, even lifesaving aide in his quest. "World War Z" is her first movie and she went through a version of bootcamp to become the resolute Segen.

Military advisor Farnsworth took Kertesz through the paces.

We put her in the platoons, taught her simple formations, with all the background and all the other extras. I only had four or five days to work with her but she took it really well," Farnsworth says.

As a rule, the filmmakers tried to cast native actors to represent the various people Gerry meets as he travels the globe.

"Everything was about authenticity, both in terms of the quality of the acting and the representation of the globe. We went to each of the places where the characters were from and dove into the local talent pool to try and find the right people. We weren't interested in people putting on accents and pretending they were from places they weren't," Dede Gardner explains.